Stabilizing apparatus

ABSTRACT

Stabilizing apparatus for the front end of a motorcycle has a pair of forwardly declining fins adjustably attached to the front forks. In another embodiment, a single fin is supported over and spaced from the front wheel. Pressure of relative wind on the fins produces downward force on the forks which tends to hold down the front end of a motorcycle.

United States Patent 1 Bringman 1 Feb. 27, 1973 STABILIZING APPARATUS[76] Inventor: Robert D. Bringman, 18600 Burbank Boulevard, Apt. 204,Tarzana, Calif. 91356 [22] Filed: Dec. 28, 1970 [21] Appl. No.: 101,689

[52] US. Cl. ..280/289, 280/213, 280/293, 280/301, 180/1 FV, 244/64,248/291 [51] int. Cl. ..B62h 7/00 [58] Field of Search ..280/289, 213,293, 295, 296, 280/301; 296/1 S; 180/1 FV; 244/64 [56] References CitedUNITED STATES PATENTS 4/1936 Backus ..296/lS 10/1971 Price ..280/2892,788,763 4/1957 Ries ..280/289 UX 1,556,902 10/1925 Beville et a1.....248/291 1,445,953 2/1923 lllgen ...l80/l FV 3,000,663 9/1961Lucchesi... ..296/1 S 1,717,515 6/1929 Linton ...180/l FV 3,545,79012/1970 Davis et al ..280/289 Primary Examiner-Leo Friaglia AssistantExaminer-John P. Silverstrim AttorneyLitt1epage, Quaintance, Wray &Aisenberg [57] ABSTRACT Stabilizing apparatus for the front end of amotorcycle has a pair of forwardly declining fins adjustably attached tothe front forks. In another embodiment, a single fin is supported overand spaced from the front wheel. Pressure of relative wind on the finsproduces downward force on the forks which tends to hold down the frontend of a motorcycle.

15 Claims, 6 Drawing Figures PATENTED FEB 2 7 I975 SHEET 1 BF 2 INVENTORROBERT D. BRINGMAN ATTORN E! PATENTED 3, 7 1 8.345

SHEET 2 BF 2 INVENTOR ROBERT 'D. BRINGMAN av ydflm M y ATTORNEY;

STABILIZING APPARATUS BACKGROUND OF THE INVENTION Recent years have seena tremendous growth in the popularity and number of two-wheeled motorvehicles, particularly motorcycles. The increased number of suchvehicles has not been confined to racing and competition events, butextends to general street and pleasure use as well.

Motorcycles have an inherent problem of stability if one of the wheelsleaves the ground. This problem becomes especially acute when the frontwheel rises. In such case, not only stability is reduced, but alsosteering capability is reduced.

Many factors influence the stability of a motorcycle. These factors maybe human, such as the experience and skill of the operator, andtechnical, such as the propensity of the front end to lift. For askilled driver, front end lift at low speeds can be tolerated. At highspeeds, front end lift becomes dangerous, even to a skilled operator.

The propensity of the front end to lift may be due to a number ofeffects. A rapidly accelerating motorcycle produces a torque about therear axle which tends to lift the front end. Often, this torque maycause the front end to raise in the air.

One of the principal causes of front wheel lift lies in the basic law offorce that every action has an equal and opposite reaction. The torquewhich turns the rear wheel forward about the rear axle in driving amotorcycle is balanced by an opposite torque which tends to turn themotor cycle and driver rearwardly about the rear axle. Usually theforward moment of the motorcycle and driver is sufficient to overcomethe rearward torque. But, when the motorcycle is driven forward, therearward torque always acts to reduce the downward force on the frontwheel produced by the combined weights of the machine and driver. Rapidaccelerations tend to displace the driver rearward, reducing his forwardmoment and downward force on the front wheel. At the same time, the hightorque which produces the acceleration, produces a greater lifting forceon the front wheel. At low speeds, for example upon starting, suchoccurences may be tolerated. At high speeds, lifting of the front wheelis extremely dangerous.

The forward leaning operator on a high speed motorcycle may induce thefront end to lift. The aerodynamic shape of the operators body maydeflect wind pressure and produce a force which has a vertical liftcomponent. High speed wind resistance forces the driver rearwardreducing his downward force on the front wheel. The planing actionbetween the wheel and ground and the aerodynamic forces on motorcycleparts magnified by the well known aerodynamic surface effects producefront wheel lifting forces. These propensities of the motorcycle frontwheel are increased by high speeds.

Thus, at high speeds, shortened operator response time and possible liftforces may impair the stability of a motorcycle.

Air foils have been known for automobiles, particularly high speedracers. Known foils may be divided into two categories, those that aremounted at the rear of a vehicle to provide increased braking andacceleration friction on the rear wheels; those mounted at the sides ofvehicles for example at quadrants. The former are usually unitary. Knownfoils of the latter type have zero angle of attack on straightaways andare positively inclined on one side when turning to prevent sway and tomaintain levelness of the vehicle. For example, when making a turn tothe right, foils on the left are given a positive angle of attack tolift the left side and to prevent it from dipping. Prior art devices areused to hold down rear wheels or to lift sides. No prior art devices areknown which are designed to overcome the long standing floating orplaning problem of high speed front end lift and steering loss. The longstanding problem remains.

SUMMARY OF THE INVENTION The invention provides stabilizing apparatuswhich may be quickly and easily attached to a front end of a vehicle,particularly a motorcycle.

This device is a safety device designed to keep the front end of amotorcycle increasingly secured down to the street as the speed of thecycle increases. The wind pressure against two fin-shaped blades mountedon either side of the front end of the motorcycle forks, angled atapproximately 45 from the horizontal but adjustable in either direction,depresses the front of the motorcycle down to increase front wheeltraction, thus avoiding high speed flotation of the front end of themotorcycle, and suppressing high speed wobbling and instability. Thismaterially increases the safety of motorcycling.

The stabilizing apparatus has forwardly declining deflection means,typically fins, which transform the pressure of wind thereon to avertical component producing a downward force on front wheels.Attachment means connect and hold the deflection means to the vehiclefor transferring downward force from the deflection means to thevehicle.

In one preferred embodiment, fins are positioned on either side of thefront wheel. In another preferred embodiment, a single fin is positionedover and spaced from the front wheel.

In preferred embodiments, adjustment means connect the attachment meansand deflection means. The adjustment means allows variance of the angleof declination for permitting downward force to be increased ordecreased per unit of pressure.

While the present invention has particular application to motorcycles,the scope of the invention allows attachment of the apparatus to othervehicles which may encounter similar problems in stability caused byhigh speed front wheel lift.

The object of the present invention is to provide simple and inexpensivemeans for increasing the front end stability of land vehicles,particularly wheeled vehicles, and especially motorcycles.

This object and other objects will become apparent from the foregoingand ongoing specification, the claims and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of amotorcycle having the stabilizing apparatus.

FIG. 2 is a detail view of the front wheel assembly of FIG. 1 showing anenlargement of the stabilizing apparatus.

FIG. 3 is a perspective detail of the deflection means.

FIG. 4 is a side elevation of embodiment having a single fin locatedover and spaced from the front wheel.

FIG. 5 is a top plan view of the embodiment shown in FIG. 4.

FIG. 6 is a front elevation of the embodiment of FIGS. 4 and 5, showingthe single fin without the braces.

DETAILED DESCRIPTION OF THE DRAWINGS Referring to FIG. 1, a motorcycle,generally indicated at 10, is shown having forwardly extending frontforks l2 and front wheel 14.

Deflection means, such as forwardly declining fins 16 are mounted onforks 12, to use relative wind to produce a downward force on the frontwheel.

As best shown in FIGS. 2 and 3, first and second forwardly declining finmeans each have downward curved portions 18. Fins 16 are mounted onforks 12 by attachment means, including pivot means 20 and its mountingmeans 22, which is connected to fork 12. Adjustment means 23 includearcuate slides 24, centered about pivots 20, mountings 26, which attachthe slides to forks 12 above the pivots, and lugs and nuts 28 whichsecure the fins at selected points along the slides.

Alternatively, the arcuate slot may be replaced by a series of detentsor openings that engage or receive a laterally extending lug of boltfixed to a fin.

The arcuate clamp may be replaced by a fixed mounting which holds thefin fixed at an angle within a predetermined angular range with respectto the ground. Angles of from 30 to 45 are desirable. Larger angles inthe range are used with smaller fins, and vice versa. When a fixedmounting replaces the adjustable one, the pivot is replaced by a fixedmounting.

Preferably, the pivot 20 is connected to the fin forward of its centerof pressure so that the relative wind tends to depress the rear portionof the fin. In some embodiments, the pivot means may be placed on thefork above the adjustable mounting.

In one embodiment, the arcuate mounting is replaced or augmented by aspring mounting which permits the fin to yield upon higher pressures ofhigher relative wind, caused by higher speeds. As the fins yield, thedownward force on the wheel increases, although not as much as would beexperienced by a rigid foil at high speeds. Drag forces also increasewith speed, but the increase is not as great with spring mounted foilsas with rigid foils.

Preferably, the forward portion of a flat or corrugated fin is curveddownward to aid in aerodynamic flow over the fin and to reduce danger ofimpaling stationary objects. For safety, the rear edge may be beaded orturned downward on itself about a small radius to reduce sharp edges.The fin may be made of any flat or three dimension material or objecthaving strength to hold its shape sufficiently to produce a downwardcomponent of force from the relative wind.

As described herein, deflection means, plates or fins mean any body ormember with the capability to produce the downward force.

In FIG. 3, the second forwardly declining fin means are shown havingelongated corrugated plates 30 which corrugations 32 running in thelongitudinal direction. As apparent in FIG. '3, preferred embodimentshave deflectors on both sidesofa front wheel.

When moving at high speeds, several forces tend to lift the front wheelof a motorcycle. One of the most serious of these forces is planing,which is created by the fluid forces which are built up by air or waterentrapped between the wheel and the ground, as the fast turning wheeldraws the fluid downward beneath the wheel. The planing force whichtends to prevent contact between the front wheel and the ground arehazardous at high speeds on dry pavements, and they are especiallyhazardous on wet pavements. A layer of water between the wheel and theground destroys all steering control. Some other possible causes ofwheel lifting forces have been identified previously as weight shift,relative wind-caused lift, and torque, which usually reaches a maximumvalue at high engine revolution, for example 6,0007,000 revolutions perminute, which are normally associated with high speeds.

When the apparatus moves at high speeds, air or relative wind impingesupon the deflection means and creates pressure thereon. This pressurecreates a force with a downward component which is useful in holding thefront wheel down on the ground, when wind, planing, torque, weightshifting and other forces tend to lift the front wheel at high speeds.

As best shown in FIGS. 4, 5 and 6, one embodiment has a single finsupported above the fender and forward of the front wheel axis byattachment means 34. The attachment means has strut means, such asstruts 36 and 38 arranged in pairs on opposite sides of the front wheel.Two flange members 40, having interior arcuate slots 42, are fixedbeneath fin 44. Fasteners pass through the arcuate slots 42 andcooperative portions of struts 36 and 38. Fasteners 46 may be tightenedto secure flanges 40 to the struts. When fasteners 46 are loosened, fin44 and flanges 40 may be moved to vary the declination of fin 44.

The embodiment as illustrated in FIGS. 4 and 5 has anti-sway means, suchas cross braces 46, connected to struts 36 and 38 for restrictingmovement of the deflection means. Preferably, the braces are connectedbetween a strut on one side of the wheel and the adjustment flange onthe other side of the wheel. The antisway braces may be connectedbetween struts on opposite sides of the wheel. Alternatively, braces areconnected between the struts and the deflection plate at a distance fromthe struts.

In all cases the deflection means are positioned at angles which producethe most satisfactory relationship between downward force and drag atthe most proba ble operating conditions. Motorcycles for highway usemight have fins adjusted for planned speed of, for example miles perhour. Racing motorcycles may have fins adjusted for higher speeds.Difference in adjustment need not be great, for wheel lifting forcestend to increase with speed at about the rates which are relative to theincreases of downward force. In both lateral and overwheel fins, theangles of declination may be permanently set with rigid connections, orthey may be adjustable in the manner shown, using slots and fasteners.Alternatively, one or more of the struts may be hinged to a fin, andadjustment may be made by sliding one of the attachments along a forkbefore tightening it in position.

While the invention has been particularly shown and described withreference to a preferred embodiment thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention.

What is claimed is:

1. Motorcycle stabilizing apparatus for a front end of a motorcyclehaving a frame, a rear wheel rotatably mounted at the rear of the frame,a fork rotatably mounted at the front of the frame, a front wheelmounted within the fork, comprising air deflection means for creating adownward force on the fork and the front wheel by the passage of airover the deflection means, said deflection means comprizing a forwardlydeclining fin means extending laterally outwardly a substantial distancefrom the longitudinal plane of said front wheel and attachment meansconnected to the air deflection means and adapted for being connected tothe fork for holding the air deflection means on the fork and fortransferring downward force from the deflection means to the fork andfront wheel of the motorcycle.

2. Apparatus of claim 1 wherein the attachment means further comprisesadjustment means connected to the deflection means and adapted for beingconnected to the fork for adjusting the deflection means with respect tothe fork for varying downward force thereon.

3. Apparatus of claim 1 wherein the deflection means comprises aplurality of fins symmetrically positioned on opposite sides of a frontwheel.

4. Apparatus of claim 1 wherein the deflection means comprises first andsecond forwardly declining fin means mounted on opposite sides of afront wheel.

5. The apparatus of claim 4 wherein the attachment means comprisesinward projecting pivot means connected to the fin means at a lowerforward portion thereof, the pivot means having mounting means adaptedfor connection to a lower forward portion of a wheel-mounting fork, andwherein the attachment means further comprises inward extendingadjusting means having an arcuate portion centered around the pivotmeans and a locking portion for connecting to the arcuate portion andhaving mountings at inward termini of the adjustment means for attachingthe adjustment means to portions of fork above the pivot means.

6. The stabilizing apparatus of claim 1 wherein the deflection meanscomprises a plate having a downward curve adjacent a forward portionthereof.

7. The apparatus of claim 1 wherein the stabilizing apparatus comprisesan elongated corrugated plate having corrugations running in alongitudinal direction.

8. The apparatus of claim 7 wherein the corrugated plate has a downwardcurving portion adjacent a forward end thereof.

9. Apparatus of claim 1 wherein the attachment means further comprisesstrut means adapted to be connected to the fork and connected to airdeflection means for holding the air deflection means in a position overand spaced from the front wheel of the motorcycle.

10. Apparatus of claim 9 wherein the strut means comprises cooperativepairs of first and second struts adapted for connection to the fork onopposite sides of the front wheel.

1. Apparatus of claim 10 further comprising ad ustment means connectedto the air deflection means and adjustably connected to distal ends ofthe cooperative pairs of first and second struts for adjusting thedeclination of the deflection means for varying the downward forcethereon.

12. Apparatus of claim 9 further comprising antisway means connected tothe strut means for restricting movement of the air deflection means.

13. Apparatus of claim 9 further comprising antisway means connected tothe strut means and connected to the deflection means for restrictingmovement of the air deflection means.

14. Apparatus of claim 9 further comprising adjustment means connectedto the deflection means and connected to the strut means for adjustingforward declination of the deflection means for varying downward forcethereon.

15. Apparatus of claim 14 wherein the adjustment means further comprisesa pair of flanges mounted on the deflection means, the flanges havingarcuate interior slots therein for permitting fasteners to passtherethrough for adjustably fastening the deflection means tocooperative portions of distal ends of first and second struts.

1. Motorcycle stabilizing apparatus for a front end of a motorcyclehaving a frame, a rear wheel rotatably mounted at the rear of the frame,a fork rotatably mounted at the front of the frame, a front wheelmounted within the fork, comprising air deflection means for creating adownward force on the fork and the front wheel by the passage of airover the deflection means, said deflection means comprizing a forwardlydeclining fin means extending laterally outwardly a substantial distancefrom the longitudinal plane of said front wheel and attachment meansconnected to the air deflection means and adapted for being connected tothe fork for holding the air deflection means on the fork and fortransferring downward force from the deflection means to the fork andfront wheel of the motorcycle.
 2. Apparatus of claim 1 wherein theattachment means further comprises adjustment means connected to thedeflection means and adapted for being connected to the fork foradjusting the deflection means with respect to the fork for varyingdownward force thereon.
 3. Apparatus of claim 1 wherein the deflectionmeans comprises a plurality of fins symmetrically positioned on oppositesides of a front wheel.
 4. Apparatus of claim 1 wherein the deflectionmeans comprises first and second forwardly declining fin means mountedon opposite sides of a front wheel.
 5. The apparatus of claim 4 whereinthe attachment means comprises inward projecting pivot means connectedto the fin means at a lower forward portion thereof, the pivot meanshaving mounting means adapted for connection to a lower forward portionof a wheel-mounting fork, and wherein the attachment means furthercomprises inward extending adjusting means haviNg an arcuate portioncentered around the pivot means and a locking portion for connecting tothe arcuate portion and having mountings at inward termini of theadjustment means for attaching the adjustment means to portions of forkabove the pivot means.
 6. The stabilizing apparatus of claim 1 whereinthe deflection means comprises a plate having a downward curve adjacenta forward portion thereof.
 7. The apparatus of claim 1 wherein thestabilizing apparatus comprises an elongated corrugated plate havingcorrugations running in a longitudinal direction.
 8. The apparatus ofclaim 7 wherein the corrugated plate has a downward curving portionadjacent a forward end thereof.
 9. Apparatus of claim 1 wherein theattachment means further comprises strut means adapted to be connectedto the fork and connected to air deflection means for holding the airdeflection means in a position over and spaced from the front wheel ofthe motorcycle.
 10. Apparatus of claim 9 wherein the strut meanscomprises cooperative pairs of first and second struts adapted forconnection to the fork on opposite sides of the front wheel. 11.Apparatus of claim 10 further comprising adjustment means connected tothe air deflection means and adjustably connected to distal ends of thecooperative pairs of first and second struts for adjusting thedeclination of the deflection means for varying the downward forcethereon.
 12. Apparatus of claim 9 further comprising anti-sway meansconnected to the strut means for restricting movement of the airdeflection means.
 13. Apparatus of claim 9 further comprising anti-swaymeans connected to the strut means and connected to the deflection meansfor restricting movement of the air deflection means.
 14. Apparatus ofclaim 9 further comprising adjustment means connected to the deflectionmeans and connected to the strut means for adjusting forward declinationof the deflection means for varying downward force thereon. 15.Apparatus of claim 14 wherein the adjustment means further comprises apair of flanges mounted on the deflection means, the flanges havingarcuate interior slots therein for permitting fasteners to passtherethrough for adjustably fastening the deflection means tocooperative portions of distal ends of first and second struts.